The Football Association (FA) has asked Manchester City boss Pep Guardiola to explain his comments about referee Anthony Taylor prior to the derby with Manchester United.
Guardiola has until 18:00 GMT on Thursday to provide his observations to the FA.
The Catalan was asked in his pre-match news conference on Friday whether he thought the fact that Taylor is from Greater Manchester was significant in terms of how he would handle the fixture.
After being told the official supports Altrincham, Guardiola said: "So no problem. He is going to try to do the best job like we try to as managers and football players.
"Even with VAR there will be mistakes but it'll reduce that issue. Taylor is going to try to make a good time.
"The important thing is focusing on our game and knowing which opponent we are going to face and that's all.
"Hopefully they can make good decisions for both sides and [it will] be a good game, like all of England and parts of Europe are going to watch us and that is an important pleasure.
"The referee doesn't want to make a mistake but knows that everybody around the world is going to watch him and he doesn't want to make mistakes. That is pretty sure.
"But if after he's a fan of United or City, everybody can be a fan wherever he wants, so no problem."
City would go on to win the derby 3-1, with goals from David Silva, Sergio Aguero and Ilkay Gundogan securing all three points for Guardiola's men.
United had pulled a goal back courtesy of Anthony Martial's penalty, although Gundogan's late strike ensured there was no way back for the Red Devils, who are now eighth in the table, 12 points behind leaders City.
Next up for Mourinho's side is a home fixture against struggling Crystal Palace, while City take on West Ham at the London Stadium.